Hi Everyone,

My name's Clint. I've already asked a few questions on this site but thought I'd start a new thread regarding the machine I'm rebuilding. It was bought new and used in a cafe for three years. After that it was stored for 18 years before I bought it. I'm really new to espresso machines. I've always loved coffee, and been really curious about the machines, but never owned one and have never been a barista. The machine is in great shape. All of the gaskets and seals are petrified though. I've ordered a bunch of parts from EPNW, but I'm sure I've forgotten a bunch of things.


I plan to use it at the local farmer's markets. I've been given permission to set up an espresso bar. I have a gas kit on the way from Astoria. Doug from Orphan Espresso said it should bolt right on.


Right now the machine is completely disassembled. Most of it has been cleaned using TSP or oxalic acid. The boiler and the copper pipes are still soaking in oxalic acid. I've learned a lot from searching around the forums and have been able to answer a lot of my questions that way. I still have a million questions but I'll just ask one now.

On the group head is a something called a retention valve. It has an adjustment screw in it and a ball bearing underneath it. The screws were frozen but I got one of them out with an impact driver. The other screw broke in half inside the valve. I've ordered a couple of screws but the valve itself doesn't seem to be available. What does the valve do, and what's the best way to get the broken screw out?

TIA. Clint

The valve acts as a pre-infusion (water flow) restrictor when the lever is raised.Hardly anyone ever adjusts them, so they're usually stuck.If the seal below the broken screw is intact, then you could leave it as is, providing it seals when in use.Can you blow thru the dipper tube, and feel the air-flow in the group bore?

If you choose to try and take out the broken screw you could try an Easy-out screw remover or similar, but if something breaks in there, you risk making things worse.Final option is to take to engineers

That little puppy sure looks like my "Antonella" a few differences but basically the same. as to the check valve...could you post a pic. I have an idea what you are talking about but a pic would help. My personal feeling is that the check valve is a one way valve so that the water in the group is not forced back into the boiler when the spring is pressurizing the water in the group. Many others seem to think it regulates the water coming in from the boiler. I'm sure it restricts flow coming in but I am not sure that is it's only function.

Here's a photo of the group head and the retention valve and screw. One of the screws broke right between the two little gaskets. Is the dipper tube the hole where the retention valve screws in or the hole where the 90 degree copper pipe screws into the tee on the group head?

Looks like I'll try an easy out.

The difficulty in getting the screw out lies in the fact that the screw does not screw OUT...the way to remove it is to take off the nut and the screw then easily screws IN for removal.

I figured that out when I was taking some tentative whacks with the impact driver. The first one screwed in easily after it broke loose, but the second one broke.

kitt wrote:The valve acts as a pre-infusion (water flow) restrictor when the lever is raised.Hardly anyone ever adjusts them, so they're usually stuck.If the seal below the broken screw is intact, then you could leave it as is, providing it seals when in use.Can you blow thru the dipper tube, and feel the air-flow in the group bore?

I'm a little confused by what "the lever is raised" means. Do you mean that the lever is in its normal position before you pull it down to preinfuse the shot, or do you mean after you raise it up to where it meets resistance to begin the shot?

How would this screw be used to adjust the pre infusion? If I backed it off, would it then allow more water in the pre infusion? How would this affect the process of making espresso?

Ooops, sorry, you're right.I got my words mixed up.I meant when the lever is lowered, or the the piston is raised.When you pull the lever down, it raises the piston above the inlet hole.Most people leave it in this position for 5-10 sec's to allow for pre-infusion, then raise the lever.

Thanks for the clarification Kitt. I did get the retention screw out with the easy out. I've got two new screws on the way so I guess I'll figure out how to adjust them once I'm up and running. I've just been going through the treasure trove of information on Orphan Espresso and came across an identical 1 group machine that Doug is selling and learned a ton of stuff just from his description.

If the weather is good tomorrow, I'm going to paint the frame of the machine. It's in good shape with the paint only flaking off in a few places. I'm going to lightly sand it to rough up the old powder coat and paint right over it with some high temp engine enamel. Maybe go with a color other than basic black. I've got all the scale off of everything except the bottom of the interior of the boiler. It's stubborn, not even the oxalic acid with hot water will break it up. I saw in another rebuild thread here that someone used muriatic acid to get off the stubborn stuff and I think I'll try that tomorrow if I can find it.

I also just found a video on Orphan Espresso regarding the Astoria Lever Group. Thanks Barb and Doug. Your site (as well as this one) is amazing.